Mount Prospect, Illinois 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

352
FXUS63 KLOT 281914
AFDLOT

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
214 PM CDT Sat Mar 28 2026

.KEY MESSAGES...

- A warming trend during the early part of next week with 60s
  Sunday and 70s Monday and Tuesday.

- Elevated fire weather conditions for the rest of today and
  possibly again on Sunday.

- Stormy weather pattern returns towards the middle of next
  week.

&&

.DISCUSSION...
Issued at 145 PM CDT Sat Mar 28 2026

Through Sunday...

It`s a quiet and seasonably cool Saturday afternoon out there.
The surface high centered over northern IL this morning has
since scooted off to the east allowing for SW winds to gust to
15 to 20 mph this afternoon while keeping the sunny skies
around. The southerly flow has also allowed afternoon dewpoints
to stay a bit higher than some of the drier model solutions were
suggesting. So while there certainly remains an elevated risk
for fire spread through this afternoon, conditions haven`t quite
warranted issuing any formal products for this.

The base of the upper trough is still working its way out of
the region. After it moves away later tonight, steady upper
height rises will promote deep warm advection into tomorrow.
Afternoon temperatures are forecast in the lower 60s beneath
partly cloudy skies. Tomorrow will be another day with SW gusts
to around 20 mph at times. Dewpoints getting up into the 30s
will lessen the fire weather risk some compared to today, but at
least a marginally elevated fire risk is anticipated tomorrow.
No rain is expected through the remainder of the weekend.

Monday through Saturday...

Attention then turns to the Monday night through Tuesday
timeframe for our next chance for thunderstorms. A stout
shortwave will trek along the US-Canadian border early next week
and phase with another wave ejecting out of the central Plains.
This will result in a quickly deepening surface low across the
upper Midwest with its cold front expected to move through the
area on Tuesday. Out ahead of the wave, strong low level warm
advection will overspread the region allowing for an
unseasonably warm day on Monday with highs forecast in the 70s
to near 80 degrees, warmest west and southwest of the Chicago
metro. The southern stream wave will drive a baroclinic zone
northward into the upper Midwest during the day and advect deep
layer Gulf moisture into the region, including surface dewpoints
into the 50s. This baroclinic zone will act as the system`s
warm front and should stall up to our north across Wisconsin for
Monday night. Atop the anomalously warm low levels, midlevel
lapse rates will be pushing 10K/km during the latter part of
Monday. Some model camps suggest we could see isolated instances
of elevated convection Monday night in the storm`s open warm
sector. However, while there will be some transient dynamic
forcing ahead of the wave, an overall lack of forcing in a
heavily capped environment should make it difficult to realize
this instability aloft and see much in the way of precip
development, if any. Better convective chances Monday night
exist north up into Wisconsin nearer to the surface front. This
thinking lines up well with the current SPC Day 3 outlook which
paints a marginal risk along and north of the IL-WI state line.
If a few storms were to get going in our local area, would need
to watch for the possibility of small hail given those lapse
rates.

A greater chance for thunderstorms will arrive on Tuesday with
the passage of the storm`s cold front. Guidance as a whole has
been trending earlier with the timing of the frontal passage,
but there are still noteworthy disagreements. The deterministic
Euro and its ensemble counterpart are the earliest calling for a
late morning through afternoon frontal passage. Other global
camps and the few regional camps that now look out into Tuesday
favor an afternoon into evening passage. The low levels still
look plenty capped ahead of the front through the morning and
even into the early afternoon, so an earlier solution could mean
overall less thunder coverage in our area, especially with
westward extent. In fact, most guidance now has the convective
line along the front forming or intensifying basically right
overhead. Once storms do mature along the boundary, parameter
spacing appears somewhat marginal for severe convection, but
seemingly ample to support strong thunderstorm winds and perhaps
some hail. Will continue to closely watch forecast trends with
this front and should have a better outlook soon as more
guidance becomes available. Daytime temperatures will also be
influenced by the timing of the cold front, but we are favored
to again see 70s to near 80 on Tuesday.

Expect cooler conditions for the middle of next week in the
wake of the front. Highs in the 40s are forecast around the area
on both Wednesday and Thursday. The baroclinic zone will get
hung up over the lower Midwest on Wednesday with some additional
precip tracking along. Some guidance suggests precip coverage
may extend far enough north to fall on parts of our CWA, but the
more likely solution is that we stay dry on Wednesday. Better
precip chances arrive on Thursday along the northern flank of
another surface low slated to track across south-central IL.
Temperatures look to return to the warmer side of normal for the
end of the week as another large synoptic system gears up to
move across the region over the weekend.

Doom

&&

.AVIATION /18Z TAFS THROUGH 00Z MONDAY/...
Issued at 1136 AM CDT Sat Mar 28 2026

No significant concerns.

A rather stout surface high has slid southeast of the terminals.
Therefore, southwest winds will pick up, and expect some gusts
up to 20-25 kt this afternoon before abating this evening. Low
level winds do pick up some overnight, which will result in
marginal low level wind shear conditions, mainly toward KRFD.
The pattern changes very little on Sunday, and southwest winds
will gust to near 20 kt in the afternoon. Scattered mid and high
clouds will stream overhead through the period.


KMD

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.

&&

$$

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